Strauss Steven H, Doerksen Allan H
Department of Forest Science, Peavy Hall 154, Oregon State University, Corvallis, OR, 97331-5705.
Evolution. 1990 Jul;44(4):1081-1096. doi: 10.1111/j.1558-5646.1990.tb03827.x.
We used restriction fragment analysis of chloroplast, nuclear, and mitochondrial DNA to study phylogeny in the genus Pinus. Total genomic DNA of 18 to 19 pine species that spanned 14 of the 15 subsections in the genus was cut with 8 restriction enzymes, blotted, and then probed with up to 17 cloned DNA fragments-which were mostly from the chloroplast genome of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco). A total of 116 shared characters, the majority representing single point mutations, were subjected to Wagner and Dollo parsimony analyses, coupled with bootstrapping and construction of consensus trees. The hard (subgenus Pinus) and soft pines (subgenus Strobus) were distinct. The soft pines in section Parrya, represented by P. longaeva, edulis, monophylla, and gerardiana, were the group closest to the hypothesized root of the genus. They were also more diverse and more closely related to the hard pines than were their descendents in section Strobus, represented by P. koraiensis, albicaulis, griffithii, and lambertiana, all of which were remarkably similar. Except for a strong clade involving P. canariensis and pinea (section Ternatae), the hard pines were weakly differentiated. The high similarity within the most speciose groups of pines (sections Strobus and Pinus) suggests that the bulk of the genus radiated relatively recently. In contrast to a recent classification, P. leiophylla was not associated with section Ternatae; instead, it appears to belong in section Pinus, and showed a high similarity to P. taeda of subsection Australes. Subsection Oocarpae, represented by P. oocarpa and radiata, appears to be a natural group, and is related to subsection Contortae, represented by P. contorta. More extensive restriction fragment studies will yield many new insights into evolution in the genus. Other methods, however, such as DNA sequencing or fine structure analysis of restriction site mutations, are likely to be necessary for rooting pine phylogenies with respect to other coniferous genera, and for estimating divergence times.
我们利用叶绿体、核和线粒体DNA的限制性片段分析来研究松属的系统发育。用8种限制性内切酶切割了松属15个亚组中14个亚组的18至19种松树的总基因组DNA，进行印迹，然后用多达17个克隆的DNA片段进行杂交，这些片段大多来自花旗松（Pseudotsuga menziesii [Mirb.] Franco）的叶绿体基因组。总共116个共享特征（大多数代表单点突变）被用于瓦格纳简约分析和多洛简约分析，并结合自展检验和构建合意树。硬松（松亚属）和软松（单维管束松亚属）明显不同。以狐尾松、食松、单叶松和乔松为代表的Parrya组软松是最接近该属假定根部的类群。它们也比以红松、白叶松、粉叶松和兰伯氏松为代表的单维管束松亚组中的后代更加多样，并且与硬松的关系更密切，而这些后代都非常相似。除了一个涉及加那利松和欧洲赤松（Ternatae组）的强大分支外，硬松的分化较弱。松属中物种最多的类群（单维管束松亚组和松亚组）内部的高度相似性表明该属的大部分是在相对较近的时期辐射演化而来的。与最近的分类不同，柔枝松与Ternatae组没有关联；相反，它似乎属于松亚组，并且与Australes亚组的火炬松高度相似。以卵果松和辐射松为代表的Oocarpae亚组似乎是一个自然类群，并且与以扭叶松为代表的Contortae亚组相关。更广泛的限制性片段研究将为该属的进化带来许多新的见解。然而，对于确定松属相对于其他针叶树属的系统发育关系以及估计分化时间，可能还需要其他方法，如DNA测序或限制性位点突变的精细结构分析。
